local voucherId = ARGV[1]local userId = ARGV[2]local stockKey = 'seckill:stock:' .. voucherIdlocal orderKey = 'seckill:order:' .. voucherIdif(tonumber(redis.call('get',stockKey)) <= 0) then    return 1endif(redis.call('sismember',orderKey,userId) > 0) then    return 2endredis.call('incrby',stockKey,-1)redis.call('sadd',orderKey,userId)return 0;